If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Having trouble with 4130 tubing

I'm having a terrible time with welding 4130 tubing, I have a Dynasty 350, I am welding 1.25 .095 wall 4130, I have cleaned it with a die grinder with a red scotchbrite pad, then wiped them with acetone. I am using about 90-100 amps, 3/32 2% with ER70S6 1/16 rod, 15 on the argon...........every weld is too hot, very gray, I couldn't get a shine out of a weld if you paid me. What the heck am I doing wrong.........very frustrated.

I have been using a gas lens but went to small cup to access small areas, didn't make any difference on the outcome, and yes I am holding the cup over the weld and slowly backing off the amperage. I am not going to heat treat the part. I really wonder if it is something in my technique. I will get pictures..........

Try the ER80s2 ....it won't really affect the color but it's what most people use. Try gas at 10-12 cfh.....a larger cup helps....if you are running to hot you can add filler faster to cool it quicker....make sure you have the post flow set for atleast 6-8 seconds and hold it after you're done....I used 2% lanthanated....this was with a Sync 250....1/16" tungsten. I had tubing in diameters from 3/16" OD up to 1" ID and wall thickness from .029-.625......the millscale will wreck havoc on you....make sure it's CLEAN CLEAN.

Originally Posted by hunter59

I have been using a gas lens but went to small cup to access small areas, didn't make any difference on the outcome, and yes I am holding the cup over the weld and slowly backing off the amperage. I am not going to heat treat the part. I really wonder if it is something in my technique. I will get pictures..........

I've switched to S-2 verses S-6, However I dont think thats your problem,
Turbo 38 was thinking the same thing as me which is use a bigger cup, If you use a small cup and try to turn up your cfm to compensater the turbulance will pull in outside air which is likely contaminating your weld.